Bug 66107 – JSC verbose debugging output sometimes doesn't work as expected.

• Component: JavaScriptCore
• Status: RESOLVED FIXED

[Filip Pizlo]

There are a few holes in our verbose debugging output:

CodeBlock::dump():
- Will crash when printing JSCell constants, if converting them to string requires calling into JS code.
- Will crash on op_new_regexp because of an out-of-bounds.

DFG verbose mode:
- Reports only the bottom address of generated code, and not the top, making it somewhat harder to mentally map executing code to the debug dumps.

[Filip Pizlo]

Created attachment 103688 [details]
the patch

[Filip Pizlo]

Comment on attachment 103688 [details]
the patch

tests pass.

[Gavin Barraclough]

Comment on attachment 103688 [details]
the patch

View in context: https://bugs.webkit.org/attachment.cgi?id=103688&action=review

> Source/JavaScriptCore/bytecode/CodeBlock.cpp:549
> +                printf("bad_regexp(%d)\n", re0);

There is something a little odd about making our dumping robust against bad regexp numbers here, since I don't think we're robust against other forms of bad bytecode in dumping.  Still, this is debug code, if this is helpful, sure! why not!

[WebKit Review Bot]

Comment on attachment 103688 [details]
the patch

Clearing flags on attachment: 103688

Committed r93238: <http://trac.webkit.org/changeset/93238>

[WebKit Review Bot]

All reviewed patches have been landed.  Closing bug.

[Darin Adler]

Moving all JavaScriptGlue bugs to JavaScriptCore. The JavaScriptGlue framework itself is long gone. And most of the more recent bugs put in this component were put there by people who thought this was for some other aspect of “JavaScript glue” and have nothing to do with the actual original reason for the existence of this component, which was an OS-X-only framework named JavaScriptGlue.